Method of forming boxes with one or more nipples



Jan.'9, 1940. Q 5 BROWN 2,186,322

G BOXES WITH ON Jan; 9, 1940. 2,186,322

METHOD 'OF FORMING BOXE WITH ONE OR MORE NIPPLES c. 5. BROWN Filed May8, 1937 5' Sheets-Sheet 2 IIIIII/IIIL J l940- c. s. BROWN 2,186,322

METHOD OF FORMING BOXES WITH ONE OR MORE NIPPLES File d May 8, 1937 3Sheets-Sheet 3 A TTORNEYS the views.

Patented 1 I S A S PAT NT FICEA a METHOD -OF" FORMING; BOXES WIT vORlMORE nI PnEs v I Charles Syracuse, N. Y. Application May 8, 1937,Serial No. 141,506

J N E' 1 Claim. 4, (ores-148.2)

, I This invention relates to-the manufacture of ing the punching outoperation 'metal boxes having nipples, as electric conduit outlet boxes,having tubular nipples forreceiving conduits. x I

It has for its object'the'method of forming conduit outletboxes, ashereinafter; set forth andclaimed.

In describing this invention, reference is hadv tov the accompanyingdrawings in which like characters designate corresponding parts in allFigures 1 and 2 are'sectional views, through'av pairof forging dies,Figure 1 showing'the operation of the dies, after they have formed theblank into box form with projecting nipples; Figure 2 being a viewsimilarto Figure 1, shownippleslinto tubular form. a Figures Band 4 aresectionallviews similar to Figures 1 and 2 of additionaldies that may beused during the punching out nipples. 1 H

Figures 5 and 6 are face views' of thejforging dies shown in Figures 3and 4, the finishedlbox being shown in broken lines,.Fi'gure 6. j

The methodaconsistsfin forming the box by forging. the same-iromya blankfirst into a box body with one side entirely open :oropensubstant iallythroughout its area, and with one or more solid nipples; then 'formingthenippl'es j with axial passages .communicating'with the inaxially, asby punching,- while holding the nip- {the nipples at IT; e a I 'Th'e useof the second pair of'dies, ll, I2 may l in some cases be necessary toequally distribute.

the nipples and during the operationof the terior of, the boxbydisplacing the metal ofthe central part of the nipples by a forceapplied ples to a predetermined shape to control the' displacement ofthe metal into asymmetrical formation, as into a tubular or cylindricalformation, and finallyremoving the portion ofthe wall of the boxlikebody in linewith the passage of the nipple or nipples, so-that thehollow nipples open in the boxlike body.

The apparatus consists of a pair dies formed with cavities shaped toforge the "blank into a box body with one or more solid; nipples"projecting therefrom and punches mov-.

able between the dies in a direction axially of punches displacing themetal of the nipples'into the nipple cavities to fill the same.

i I and} designate, respectively,'the opposing forging .die sectionsformed with a cavity be-v tween them for shaping the box 3 and the solidnipples 4. The dieQl-is provided with a projection or core 5 for formingthe interior of the body'of the box. The portions Got the cavities ofthe solid foperationof the of forging forming the nipples 4 are of suchsize ordiamdisplaced by the forging operation forming the nipples, sothat there is a clearance in the portions .6, as at 1.

8 are punches mounted between the die sec tions l, 2, there being onepunch for each nipple..These punches are forced inwardly by any tiallyfill the portions 6 of the cavities so that the walls of the portionsiisymrne'trically shape the nipples during the punching operation. I

As seen-in Figure '2; the punching operation terminates a little shortof the inner end of the nipple or shortpofgthe interior ofthe boxpor-,tion-of the blank, leaving a .thinslug at 9, which may be afterwardsremoved in any suitable mannerjas by additional punchinsybor ng ordrilling,

after the blank'is removed from the dies How-- ever, as seeninFigures 3and 4, the blank, after "it is forged, with the solidnipples, as inFigure 1,

veteras not'to be'completely filled by the metal suitable means axiallyinto-the nipples 4 and displace the metal of the nipples, so as tosubstanmay beplaced in another pair jofdies II and l2 fitting thepreformed blank, after it is taken "from the dies 1,2, and thecor'epiece l5 isformed with transverse passages 20. axially alined with thesolid-nipples 4. iThe' corepiece is also'formed with a: cavitylll5a,with. whichfthe transverse passages 20 communicate a to receive themetal displaced while thepunches are working in the transverse passages20;

the metalinto the nipple cavities when it is unequally distributed in-these cavities, after the ;firstforging. operation by the dies l 2'. l1 l8 designates the punches suitably mounted between the sections I! and{2 in passages alined with the nipples! and .the transverse passages 20,these punches havingreduced end portions I9 for .entering' the passages20, which are of less diameter than the finalfbor'e'of the nipples.

Whenforce is applied to move the punches l8 inwardly, the'bod yf of eachpunch of larger diameter forms the axial passageof the nipple and theportion [9 of smaller diameter moves into the passage -2il,. and in "sodoing provides 'an annular shoulder -2l at the" inner end I of thenipple againstwhi'ch the end of the conduit received in the. nipple,abuts. The metal displaced duringj the'. punching operation fills up theclearance l1, so that the cavity portions form the nipple to apredetermined shape and size during the displacement of the metal by thepunches l8. l

The box, as finally formed, is shown in dotted lines in Figure 6 as anelongated box open at one side, with a nipple 4 at each end and laterally extending nipples between its ends, this being one conventional formof electric conduit outlet box.

Under the requirements of the Board of Underwriters, electric conduitoutlet boxes must stand certain tests, as tostrains, etc., and an outletbox formed by this method-and apparatus What I claim is: l l

The method of making metal boxes open at one side with one or moreconduit-receiving nipples, consisting in forging a blank into a boxlikebody having one side open substantially throughout the area of saidside, and one or more solid projecting nipples, then punching out thenipple or nipples in an axial direction from their outer ends inwardlywhile holding the nipple or nipples and the body to a predeterminedshape during the punching operation, and finally cuttingthe wall ofmetal at the inner ends of the nipple or nipples so that the passage orpassages of thelnipple ornipples formed by the punchingdisplacingoperation, open into the interior of the body.

CHARLES S. BROWN.

